1. Field of the Invention
The present invention relates to a video image data reproducing apparatus, and particularly to a reproducing apparatus for reproducing main contents and sub-contents.
2. Description of the Related Art
A recording medium such as a DVD (Digital Versatile Disc) records main contents and sub-contents. The main contents include video images (e.g., movie pictures and self-taken record pictures). The sub-contents include audio (e.g., multi-language dubbed audio) and captions (e.g., multi-language captions). The audio and caption data is reproduced in a selected language which is selected by user selection through menu operation (see, e.g., Japanese Patent Application Laid-Open No. H08-263969 and its corresponding U.S. Pat. No. 5,778,142).
The recording medium also records caption management information and caption stream data. The reproducing apparatus reads out caption stream data which corresponds to an ID number selected by a viewer, from the recording medium, and decodes the read-out caption stream to display the caption stream data at a position and time determined based on the management information, with the caption stream data being overlapped with main contents (pictures).
Further, the recording medium also records audio management information and audio stream data. The reproducing apparatus reads out the audio stream data which corresponds to an ID number selected by a viewer, from the recording medium, and decodes the read-out audio stream data to display the audio stream data in coordination with main contents (pictures) at a time which is determined based on the management information.
On the other hand, an event operation may be performed so that a menu is displayed halfway during reproduction to wait for a user's menu selection operation and to accept the menu selection operation before resuming the reproduction of video images depending on the selected item. For example, such operation provides reproduction of a plurality of video image data, branch operation by user input and the like (see, Japanese Patent Application Laid-Open No. H10-271452).
Actually, the technical characteristics of the above patent document are that the sub-contents are reproduced in synchronization with the main contents. For example, traditional audio and captions (sub-contents) are synchronously reproduced with the movie (main contents).
However, there are some situations where the sub-contents should not be reproduced in synchronization with the main-contents. For example, as shown in FIG. 20, it is assumed that a request is made for reproduction of a contents explanation (sub-contents) 1302 which has detailed explanation of a movie (main-contents) 1301. The contents explanation here has a feature that provides explanation for the location of the movie, and a larger amount of information as compared to the captions. In this respect, if a contents explanation (sub-contents) is synchronously reproduced with the movie (main contents), it could be switched to the next contents explanation before the viewer reads through the contents explanation (sub-contents). In the techniques described in the above patent document, the main contents will proceed independently of features of sub-contents. That is, it is not possible to reproduce the main contents and the sub-contents in coordination with the features of the sub-contents.